The present invention relates to a showcase lock for by-pass type sliding doors such as the sliding glass doors used in glass showcases. Such showcase locks generally include an elongated keeper that can be attached to the inner door and a separate lock member that is adjustable along the keeper to lock the doors in a closed position. Showcase locks of the type shown in U.S. Pat. Nos. 2,050,696; 2,172,208 and 2,878,663 require some clearance between the keeper and the inner panel to allow mounting of the lock on the keeper, and the keepers in these patents are attached at only one end by a clip or clamp to the edge portion of the inner closure panels. Clip-on type keepers can move or shift relative to the inner door and present problems not only because they can become tilted or even dislodged from the inner door during installation, but also because they can cause chipping of the edges of glass doors, if they are not properly positioned when the lock is installed. My prior U.S. Pat. No. 3,931,723, discloses a showcase lock in which the keeper is adhesively secured along its entire back side to the face of the inner panel so that it cannot move or shift relative to the inner panel. However, my prior patent required a special plunger type lock in which the lock plug could be moved both axially and rotationally to first shift the latch toward the keeper and then turn the latch into locking engagement with flanges on the keeper.
It is an object of this invention to provide a showcase lock having an improved arrangement for slidably mounting the lock on the front side of the keeper for locking in adjusted positions therealong whereby the back side of the keeper can be adhesively bonded to the face of the door.
Another object of this invention is to provide a showcase lock for sliding doors in which the keeper has a row of stops intermediate its side edges and the lock has an improved latch and latch actuator for moving the latch into and out of engagement with the stops in response to turning of a key operated plug.
Still another object of this invention is to provide a showcase lock for sliding doors in which the lock is movably retained by a chain on one of the doors when not in use.
Other objects of this invention are to provide a showcase lock for by-passing type doors which can be economically manufactured, which can be easily installed on the doors without use of tools, and which substantially eliminate chipping or breaking of glass type closure panels by the showcase lock.